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581.
IdaRose is a late-maturing, potato variety with round, dark red tubers. It has high yield potential and exceptionally long tuber dormancy. IdaRose was released in 2000 by the USDA/ARS and the experiment stations of Idaho, Oregon, and Washington. It resulted from a 1982 cross of Sangre and TXA218-7. IdaRose is suited for use in both the early summer and storage fresh markets. Tuber yield of IdaRose is higher than that of Dark Red Norland and Sangre. It has yield potential similar to or slightly lower than Red LaSoda. Tubers of IdaRose have good internal and external quality. Culinary quality of boiled, baked, and micro-waved IdaRose tubers is excellent. It has moderate resistance to growth cracks, hollow heart, and other defect problems. IdaRose is susceptible or moderately susceptible to most common field diseases of potato. Tubers of IdaRose have dry matter content (19.2%) similar to other standard red varieties, and have a relatively high concentration of sugars and low concentration of glycoalkaloids (2.4 mg/100 g).  相似文献   
582.
Radiographic, myelographic and computed tomographic (CT) studies from sixteen dogs with histologically diagnosed vertebral or spinal cord neoplasia (seventeen lesions) were retrospectively evaluated. Radiographs were compared with CT images to evaluate vertebral bony changes (bone production, lysis or both). Myelographic and CT images were evaluated to separate lesions into one of three categories, extradural, intradural/extramedullary, or intramedullary. These findings were compared to histologic tumor type from surgical or necropsy samples. Histologically, seven lesions were vertebral tumors and were classified as extradural lesions; ten lesions were spinal cord tumors of which eight were classified as intradural/extramedullary and two as intramedullary. Using CT, the amount of bony change associated with extradural lesions was greater than or equal to the amount of bony change visualized using radiographs. Myelography more correctly differentiated between intradural/ extramedullary and intramedullary lesions than did CT, although three open diagnoses detracted from the CT results. This study suggests that when evaluating extradural lesions, the amount of bony change was better visualized using CT than survey radiographs. Myelography was better when compared to CT for classifying spinal cord lesions, however, standardization of the CT imaging protocol may help determine the specific clinical indications for using CT in dogs with suspected vertebral or spinal cord tumors.  相似文献   
583.
Fullerene pipes   总被引:10,自引:0,他引:10  
Single-wall fullerene nanotubes were converted from nearly endless, highly tangled ropes into short, open-ended pipes that behave as individual macromolecules. Raw nanotube material was purified in large batches, and the ropes were cut into 100- to 300-nanometer lengths. The resulting pieces formed a stable colloidal suspension in water with the help of surfactants. These suspensions permit a variety of manipulations, such as sorting by length, derivatization, and tethering to gold surfaces.  相似文献   
584.
The release of three new potato (Solarium tuberosum L.) cultivars, Bannock Russet, Gem Russet, and Summit Russet, with unique plant growth characteristics, necessitates the development of appropriate N fertilizer recommendations. These three new cultivars, along with the standard cultivar, Russet Burbank, were treated with four N rates (0, 100, 200, and 300 kg N ha?1) using two different application timing procedures (“early,” with two-thirds N applied preplant, and “late,” with one-third applied preplant). Measurements included total and U.S. No. 1 yields, petiole NO3-N concentrations, and net returns derived from economic analysis using a processing-based contract. Each of the four cultivars showed a unique response to N application treatments. Bannock Russet achieved maximum yield and net returns with relatively small amounts of N fertilizer. It also showed no response to N application timing and had moderate NO3-N sufficiency concentrations early in the season, that decreased markedly late in the season. Gem Russet N requirement for maximum yield was similar to that of Russet Burbank, but required a higher amount of N for maximum net returns. Gem Russet also showed no response to application timing and had NO3-N sufficiency concentrations similar to or slightly higher than those of Russet Burbank. Summit Russet showed a strong trend for improved N use-efficiency when most of the N was applied early. On the other hand, analysis of net returns revealed a trend for greater profitability for Summit Russet when the majority of N was applied during tuber bulking. Petiole NO3-N sufficiency concentrations for Summit Russet were generally higher than those for the other three cultivars. In comparison with some earlier studies with Russet Burbank, this research suggested lower optimal N rates and petiole NO3-N sufficiency concentrations.  相似文献   
585.
U.S. seafood consumption has changed dramatically in recent decades and has become increasingly dominated by the consumption of a limited number of species that are primarily imported and predominantly sourced from aquaculture. In getting to this point, the United States has been, and still is, at the forefront of some of the most important trends in global seafood markets. Hence, discussing the factors influencing U.S. seafood consumption patterns is an interesting and informative endeavor and will most likely also have strong predictive power for the continued development of seafood markets in the United States. In this article, we will discuss the transitions in the U.S. seafood market, primarily focusing on the period from 1990 to the present, highlighting the main factors that facilitated this development. This article provides an overview of U.S. landings, aquaculture production, exports, and imports and also explores contributing trends in global export and import markets. This will be followed by a discussion of U.S. per capita consumption patterns and an examination of the consolidation of species consumed over time. Finally, implications for future trends in seafood consumption and production are discussed.  相似文献   
586.
Mutation breeding was investigated as a method to improve important quality traits in the cultivar Russet Burbank. Two thousand excised eyes were irradiated with a gamma-ray dose of 35 Gy. The irradiated eye pieces were planted directly to the field and approximately three tubers from each of resulting plants were harvested and, constituted the initial 6000 clone selection population. The M1V1 tubers and subsequent clonal progeny were subjected to six generations of evaluation and selection. Selection criteria included appearance, resistance to blackspot bruise, french fry color following storage at 4 C, and specific gravity. At the end of six selection cycles, five mutants remained from the original population of approximately 6000. These included two mutants selected for improved appearance (RBM161 and RBM366), one for resistance to blackspot bruise (RBM166), one for french fry color (RBM13), and one for specific gravity (RBM170). An analysis of variance over three years showed that the three mutants selected for internal quality traits (RBM13, RBM166, and RBM170) produced lower yields in comparison with two Russet Burbank control clones. RBM161 was selected for its heavier, more uniform russet skin, and appeared to be similar to the mother clone for important agronomic and quality traits. RBM366 was selected for improved appearance, typified by higher breeders preference scores and a lower percentage of tubers exhibiting external defects. It also produced higher total and U.S. No. 1 yields than the controls.  相似文献   
587.
Objective To describe proctitis associated with chlamydial infection in a koala.
Design A pathological study  

Animal


A free living, male koala aged 17 years.
Procedure Rectum was examined histologically and chlamydial organisms visualised using Giminez stain and an immunoperoxidase staining method using an anti- Chlamydia lipopolysaccharide (genus specific) antibody.
Results An aged koala presented for euthanasia was found to have asymptomatic chronic proctitis, cystitis, prostatitis, urethritis and conjunctivitis associated with chlamydial infection. Inflammation was severe in the terminal rectum and extended into the proximal common vestibule. Chlamydial organisms were visualised in the rectal surface epithelium using Giminez stain and an immunoperoxidase staining method. Organisms were also detected in the epithelium of the bladder, prostate and urethra.  

Clinical Implications


Possible modes of transmission for the rectal infection are direct sexual transmission or ascending infection by organisms shed from the urogenital tract into the common vestibule. Previously unreported chlamydial proctitis in the koala may represent a potential reservoir of infection for other koalas.  相似文献   
588.
Mice homozygous for a single tyrosine mutation in LAT (linker for activation of T cells) exhibited an early block in T cell maturation but later developed a polyclonal lymphoproliferative disorder and signs of autoimmune disease. T cell antigen receptor (TCR)-induced activation of phospholipase C-gamma1 (PLC-gamma1) and of nuclear factor of activated T cells, calcium influx, interleukin-2 production, and cell death were reduced or abrogated in T cells from LAT mutant mice. In contrast, TCR-induced Erk activation was intact. These results identify a critical role for integrated PLC-gamma1 and Ras-Erk signaling through LAT in T cell development and homeostasis.  相似文献   
589.
An investigation of the reproductive performance of first parity sows is described. In a retrospective study it was found that the size of the second litter was significantly greater in those sows with a prolonged weaning to oestrus interval of more than 15 days. Deliberately delaying mating until at least 12 days after weaning produced a similar increase in second litter size. This improvement was not associated with an increase in ovulation rate.  相似文献   
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